The present invention relates to a gas turbine engine, and more particularly to a rotor blade thereof.
Gas turbine engines often include a multiple of rotor assemblies within a fan, compressor and turbine section. Each rotor assembly has a multitude of blades attached about a circumference of a rotor disc. Each of the blades is spaced a distance apart from adjacent blades to accommodate movement and expansion during operation. Each blade includes an attachment section that attaches to the rotor disc, a platform section, and an airfoil section that extends radially outwardly from the platform section.
When engine weight becomes a concern, emphasis is directed toward the reduction of blade weight since every one pound of weight in the set of blades is worth about three pounds of weight in the rotor disk due to centrifugal forces. Weight is typically removed from the blade by thinning airfoil walls and ribs until a minimum thickness is achieved from a manufacturing and structural standpoint.
Although there may be significant mass in the attachment region of the blade, this mass is required to prevent fracture of the blade when centrifugal and airfoil bending loads are applied.